Arimidex inhibition on proliferation of human breast solid tumors measured by ATP bioluminescence

Abstract

To determine the degree of Arimidex (Anastrozole) inhibition on proliferation of human breast solid tumors in vitro by ATP bioluminescence assay. Breast cancer solid tumors with different hormone receptors and grading were collected from 38 Chinese women with invasive breast cancers. Tumors were treated with three concentrations of Arimidex (1.5 mM, 15 mM and 150 mM). ATP bioluminescence assay was used to measure the metabolic rate in order to determine the degree of inhibition of Arimidex on the breast cancer tumors by comparing to the untreated tumors. 15 mM Arimidex shows greatest inhibitory effect on the proliferation of solid tumors with ER-postive/PR-positive. It can also inhibit the growth of metastatic tumors and tumors with HER-2/neu expression. It shows greater inhibitory effect in lower grading of tumors then higher. Arimidex may effectively inhibit the growth of breast tumors in in vitro system by inhibiting aromatase and block estrogen dependent tumor growth.